I just found a live stream in HD of a spot near Shimbashi station.

Tokyo: Rail Tracks Live Webcam - Japan - World Cams

I don't know all the lines which run through this point, but watching it really shows how busy it is. The bullet trains are going slowly because it's close to Shimbashi station.

1. The elevated line on the left is the fully automated line to Odaiba.
2. The leftmost pair of tracks are the Tokaido bullet train line between Tokyo and Osaka.
3. The rightmost pair of tracks is for the Yamanote loop line, probably the busiest train line in the world. According to Wikipedia, it carried over a billion passengers in 2015.
4. The middle lines are for trains such as the Yokosuka line and the Tokaido main line as well as others that share the Tokaido main line.

It's worth watching for a few minutes, especially if it's a busy time. It's amazing seeing successive bullet trains only a minute or two apart!

That's pretty cool Rob - thanks for sharing.

You're welcome! The Yamanote line trains can be identified by the pale green band across the front. I think all the Tokaido bullet trains will be 700 series or N700 or N700A, and all white. There's a yellow Shinkansen called "doctor yellow" which tests the tracks and overhead wires, but I understand that it will be retired because they've built the means to monitor everything into all the trains.